Displaying compund images

[smita]

I wish to display 2 pictures on screen at the same time. The actually time of the main picture been displayed is 1500ms but the other picture is 30ms and mask is 200ms. How do i continue displaying the main picture for a longer time?

[jarvis24]

Do the images overlap? i.e., the 30ms one and the 1500ms one or are they located on different areas of the screen? If they are in different areas, you could display the both simultaneously using a TIME value of 0 between them. List the 1500ms image first, with a Time value of 0. Then list the 30ms image with a Time value of 30. Then locate and display a black (or blank) image in the same location as the 30ms image in order to give the illusion of it disappearing while the 1500ms image stays on screen. You would want ti use a clear value of 0 in all your location columns for this, i.e., "x, y, 0" to ensure the screen is not cleared completely at any point during the trial.